"Singing with Carrie Underwood is very, very intimidating -- I mean, I'll be honest," the songstress dishes to Yahoo. "She is an amazing vocalist. I'm a big fan of hers, and asking her to do this was nerve-racking."

Lambert dishes that worked up the courage to ask the 'Blown Away' hitmaker to share song space via an email.

"I sent her an email ... a long, blabbing email about if she wanted to sing on the record, it could be cool, but maybe she didn't want to, and if she liked the song, but she didn't have to like the song ... when I sent it, I thought, 'This sounds ridiculous,'" Lambert shares.

The sassy songstress' forthright attitude paid off -- the two Southern gals hit the studio together, much to the delight of fans. "We're really rocking in country music and we're coming together as a force ... I'm ready to rock and singing with Carrie really pushes me," she says.

The Lambert/Underwood collaboration, called 'Something Bad,' comes at the right time, bringing girl power to the stage with force.

"It's been too long since two girls in our genre have come together like that," Lambert concludes, "especially on a song that's kind of in your face."